From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6A58727A46A; Tue, 21 Oct 2025 20:08:17 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761077297; cv=none; b=e3nbyGevS07zxJHo9DteR9PjpOkiN25ayJozao5SlJ2SWdXmaJvR6rMv/vc1CN3PiN5oYfbXOBrsPf/ruY5OCih8UDVSU08WeNJEZsha4/liW0RGDlZc02GRS6f1WEoz4ieW8neBrKNogIEAAVER0Zq1EYT75aS7drhGk4L9Q7M= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761077297; c=relaxed/simple; bh=8cv7RBB4i90F2wYPglkkjj5ItIZJI4B+4oe5GeYOeYA=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=ThExfNCuPgEWvk95MhgsuVmOv5csEz/2VyKlf20smvm5KXv9SrMc7X5uZ+iZcaWEKHiKxQJ1H8Gf+1csxtLPPdDYmq8s18SpnFZSmbrjXWl+70Y3DhSs1nrF/YnSQcUgXwUwMO7qEIiUtmbRmo3KiHSMJJmepI9GzHuAiTegl50= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=WgLlV8Za; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="WgLlV8Za" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E4F97C4CEF1; Tue, 21 Oct 2025 20:08:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1761077297; bh=8cv7RBB4i90F2wYPglkkjj5ItIZJI4B+4oe5GeYOeYA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=WgLlV8ZaQ9vSyN9oCtSf6edbMcV4dJeCrWxTQ1H5ecO2LwF4FR2gAvGkkDfEbYsSr MYTtb0WKV3YtvjXjUrIWLtTvWAgbiBnJrq5pyVFexaghoAdm3t2QWmOpH8E6QFdGDD wTzuL0NVxcHaqXLWfSUDr5vomL0fOZCErUy/NTEI= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Markus Schneider-Pargmann , Marc Kleine-Budde , Sasha Levin Subject: [PATCH 6.17 061/159] can: m_can: m_can_handle_state_errors(): fix CAN state transition to Error Active Date: Tue, 21 Oct 2025 21:50:38 +0200 Message-ID: <20251021195044.682143707@linuxfoundation.org> X-Mailer: git-send-email 2.51.1 In-Reply-To: <20251021195043.182511864@linuxfoundation.org> References: <20251021195043.182511864@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.17-stable review patch. If anyone has any objections, please let me know. ------------------ From: Marc Kleine-Budde [ Upstream commit 3d9db29b45f970d81acf61cf91a65442efbeb997 ] The CAN Error State is determined by the receive and transmit error counters. The CAN error counters decrease when reception/transmission is successful, so that a status transition back to the Error Active status is possible. This transition is not handled by m_can_handle_state_errors(). Add the missing detection of the Error Active state to m_can_handle_state_errors() and extend the handling of this state in m_can_handle_state_change(). Fixes: e0d1f4816f2a ("can: m_can: add Bosch M_CAN controller support") Fixes: cd0d83eab2e0 ("can: m_can: m_can_handle_state_change(): fix state change") Reviewed-by: Markus Schneider-Pargmann Link: https://patch.msgid.link/20250929-m_can-fix-state-handling-v4-2-682b49b49d9a@pengutronix.de Signed-off-by: Marc Kleine-Budde Signed-off-by: Sasha Levin --- drivers/net/can/m_can/m_can.c | 53 +++++++++++++++++++++-------------- 1 file changed, 32 insertions(+), 21 deletions(-) diff --git a/drivers/net/can/m_can/m_can.c b/drivers/net/can/m_can/m_can.c index fe74dbd2c9663..4826b8dcad0f7 100644 --- a/drivers/net/can/m_can/m_can.c +++ b/drivers/net/can/m_can/m_can.c @@ -812,6 +812,9 @@ static int m_can_handle_state_change(struct net_device *dev, u32 timestamp = 0; switch (new_state) { + case CAN_STATE_ERROR_ACTIVE: + cdev->can.state = CAN_STATE_ERROR_ACTIVE; + break; case CAN_STATE_ERROR_WARNING: /* error warning state */ cdev->can.can_stats.error_warning++; @@ -841,6 +844,12 @@ static int m_can_handle_state_change(struct net_device *dev, __m_can_get_berr_counter(dev, &bec); switch (new_state) { + case CAN_STATE_ERROR_ACTIVE: + cf->can_id |= CAN_ERR_CRTL | CAN_ERR_CNT; + cf->data[1] = CAN_ERR_CRTL_ACTIVE; + cf->data[6] = bec.txerr; + cf->data[7] = bec.rxerr; + break; case CAN_STATE_ERROR_WARNING: /* error warning state */ cf->can_id |= CAN_ERR_CRTL | CAN_ERR_CNT; @@ -877,30 +886,33 @@ static int m_can_handle_state_change(struct net_device *dev, return 1; } -static int m_can_handle_state_errors(struct net_device *dev, u32 psr) +static enum can_state +m_can_state_get_by_psr(struct m_can_classdev *cdev) { - struct m_can_classdev *cdev = netdev_priv(dev); - int work_done = 0; + u32 reg_psr; - if (psr & PSR_EW && cdev->can.state != CAN_STATE_ERROR_WARNING) { - netdev_dbg(dev, "entered error warning state\n"); - work_done += m_can_handle_state_change(dev, - CAN_STATE_ERROR_WARNING); - } + reg_psr = m_can_read(cdev, M_CAN_PSR); - if (psr & PSR_EP && cdev->can.state != CAN_STATE_ERROR_PASSIVE) { - netdev_dbg(dev, "entered error passive state\n"); - work_done += m_can_handle_state_change(dev, - CAN_STATE_ERROR_PASSIVE); - } + if (reg_psr & PSR_BO) + return CAN_STATE_BUS_OFF; + if (reg_psr & PSR_EP) + return CAN_STATE_ERROR_PASSIVE; + if (reg_psr & PSR_EW) + return CAN_STATE_ERROR_WARNING; - if (psr & PSR_BO && cdev->can.state != CAN_STATE_BUS_OFF) { - netdev_dbg(dev, "entered error bus off state\n"); - work_done += m_can_handle_state_change(dev, - CAN_STATE_BUS_OFF); - } + return CAN_STATE_ERROR_ACTIVE; +} - return work_done; +static int m_can_handle_state_errors(struct net_device *dev) +{ + struct m_can_classdev *cdev = netdev_priv(dev); + enum can_state new_state; + + new_state = m_can_state_get_by_psr(cdev); + if (new_state == cdev->can.state) + return 0; + + return m_can_handle_state_change(dev, new_state); } static void m_can_handle_other_err(struct net_device *dev, u32 irqstatus) @@ -1031,8 +1043,7 @@ static int m_can_rx_handler(struct net_device *dev, int quota, u32 irqstatus) } if (irqstatus & IR_ERR_STATE) - work_done += m_can_handle_state_errors(dev, - m_can_read(cdev, M_CAN_PSR)); + work_done += m_can_handle_state_errors(dev); if (irqstatus & IR_ERR_BUS_30X) work_done += m_can_handle_bus_errors(dev, irqstatus, -- 2.51.0